Quantitative assessment of the role of local and neighborhood features on the grain-scale response of Inconel 718

High-resolution digital image correlation (HR-DIC) was performed in situ on Inconel 718 samples as they were plastically deformed in the small-strain regime. The two samples examined underwent two different heat treatments to produce microstructures with and without extensive precipitation. After HR-DIC data processing was completed to extract quantitative 2D strain and slip band maps, statistical correlation analyses were performed between local and neighborhood microstructural and micromechanical features (determined with electron backscatter diffraction) and both mean and maximum strains measured within the grains. For the solutionized sample, 947 grains and neighborhoods were studied, while for the precipitation hardened sample, 565 grains and neighborhoods were studied. From the analyses of the grains and neighborhoods, quantitative relationships were found between grain size and strain localization; the effects of local and neighborhood directional modulus and Schmid factor on mean and maximum strains; and slip transmission and strain localization.